Diesel chat transfered from "Glow Engines - Fox"
05-09-2016, 04:36 PM
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Diesel chat transfered from "Glow Engines - Fox"
Quote from 1QwkSport2.5r in "Glow Engines - Club Fox", to Bill Adair". Repeated here because that thread had drifted into diesel fuel mixes!
"I've read the MSDS for the JD ether and even though the sheet says the fluid is 80% ether, the other 20% is basically propellant which I believe is propane. There isn't any oil or lubricant in it AFAIK. I was advised to treat the liquid portion as basically straight ether. I mix my fuel at about 31% ether and most of my conversions will hand start. I haven't quite mastered getting the perfect prime, so I probably tend to either under-prime or over-prime. So far not enough to hydraulic lock, but wet enough that they don't start easily. I kinda went backwards somewhat and started using a starter and leaving the compression at the "run" setting until the engine fires and adjust compression and needle valve when the engine warms up. I usually find I have to increase compression a half turn to get the burping to stop and actually build up enough heat to be able to properly adjust the compression and needle valves. I'm still new to diesels, so I'm still working to find my comfort zone with them."
Hi Sport,
I've heard almost the same thing from very knowledgeable fellows here in this section, except they said to treat the 20% propellant as Kerosene. It's not Kerosene of course, but Propane would likely burn in the fuel mix with similar results.
Most of my fuel has been the old English mix of equal parts, with 1-2% Amsoil Cetane Booster added, so I still ended up with enough Ether for starting, but not as much as I thought.
I'll let you know the results when I run the new batch.
Bill
"I've read the MSDS for the JD ether and even though the sheet says the fluid is 80% ether, the other 20% is basically propellant which I believe is propane. There isn't any oil or lubricant in it AFAIK. I was advised to treat the liquid portion as basically straight ether. I mix my fuel at about 31% ether and most of my conversions will hand start. I haven't quite mastered getting the perfect prime, so I probably tend to either under-prime or over-prime. So far not enough to hydraulic lock, but wet enough that they don't start easily. I kinda went backwards somewhat and started using a starter and leaving the compression at the "run" setting until the engine fires and adjust compression and needle valve when the engine warms up. I usually find I have to increase compression a half turn to get the burping to stop and actually build up enough heat to be able to properly adjust the compression and needle valves. I'm still new to diesels, so I'm still working to find my comfort zone with them."
Hi Sport,
I've heard almost the same thing from very knowledgeable fellows here in this section, except they said to treat the 20% propellant as Kerosene. It's not Kerosene of course, but Propane would likely burn in the fuel mix with similar results.
Most of my fuel has been the old English mix of equal parts, with 1-2% Amsoil Cetane Booster added, so I still ended up with enough Ether for starting, but not as much as I thought.
I'll let you know the results when I run the new batch.
Bill
05-09-2016, 06:57 PM
#2
Thanks for copying that stuff over, Bill. I'm sure this has been discussed here before but I'll post it anyway.
John Deere Starting Fluid MSDS: http://www.onboces.org/safety/msds/J...ng%20Fluid.pdf
It shows CAS # 60-29-7 at 80-90% (DiEthyl Ether)
CAS 74-98-6 at .10-10% (Propane)
CAS 124-38-9 at 5-10% (Carbon Dioxide)
CAS 106-97-8 at .10-10% (Butane)
CAS 64224-52-5 at .10-10% (B200 Base Oil)
Im no scientist, and I don't have the lab equipment to break this stuff down and determine exact quantities of each component is in the stuff.... What I do know is the B200 Base Oil is used for a whole page worth of uses including fuel, lubricant, rust inhibitor, among many others. I've milked enough JD Ether cans to know this stuff evaporates so clean, there's virtually no residue whatsoever. I believe the contents of the final product has virtually no oil that could be "substituted" for kerosene. Obviously CO2 is inert and doesn't burn, so in theory at maximum, the JD spray is 94.8% pure ether. The propane and butane will gas off over time, it is a fuel indeed, but I don't think there's as much of this as people think.... I had been considering calling the JD spray as -100% ether and based my mixtures off of that premise.
Thoughts?
John Deere Starting Fluid MSDS: http://www.onboces.org/safety/msds/J...ng%20Fluid.pdf
It shows CAS # 60-29-7 at 80-90% (DiEthyl Ether)
CAS 74-98-6 at .10-10% (Propane)
CAS 124-38-9 at 5-10% (Carbon Dioxide)
CAS 106-97-8 at .10-10% (Butane)
CAS 64224-52-5 at .10-10% (B200 Base Oil)
Im no scientist, and I don't have the lab equipment to break this stuff down and determine exact quantities of each component is in the stuff.... What I do know is the B200 Base Oil is used for a whole page worth of uses including fuel, lubricant, rust inhibitor, among many others. I've milked enough JD Ether cans to know this stuff evaporates so clean, there's virtually no residue whatsoever. I believe the contents of the final product has virtually no oil that could be "substituted" for kerosene. Obviously CO2 is inert and doesn't burn, so in theory at maximum, the JD spray is 94.8% pure ether. The propane and butane will gas off over time, it is a fuel indeed, but I don't think there's as much of this as people think.... I had been considering calling the JD spray as -100% ether and based my mixtures off of that premise.
Thoughts?
05-09-2016, 10:49 PM
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Sport,
Propane and Butane are both flammable, but just how much might be left in suspension is beyond me. I'm going to treat the fluid as 80% Ether, and see how it performs, both in ease of starting, and power output. Suspect I'll find the best compromise is somewhere between 80-90%.
Diesel fuel blending would be so much easier, if pure Di-ethyl Ether was still available to us non-drug users. Damn those drug users!
Bill
Propane and Butane are both flammable, but just how much might be left in suspension is beyond me. I'm going to treat the fluid as 80% Ether, and see how it performs, both in ease of starting, and power output. Suspect I'll find the best compromise is somewhere between 80-90%.
Diesel fuel blending would be so much easier, if pure Di-ethyl Ether was still available to us non-drug users. Damn those drug users!
Bill
05-10-2016, 12:48 AM
#5
I'm very sure treating it as 80% ether will work fine - if the concentration is a tad higher than 80%, would engine power go down a little since the kerosene/parafin/etc. level would be lower?
05-10-2016, 12:53 AM
#6
Sport,
Propane and Butane are both flammable, but just how much might be left in suspension is beyond me. I'm going to treat the fluid as 80% Ether, and see how it performs, both in ease of starting, and power output. Suspect I'll find the best compromise is somewhere between 80-90%.
Diesel fuel blending would be so much easier, if pure Di-ethyl Ether was still available to us non-drug users. Damn those drug users!
Bill
Propane and Butane are both flammable, but just how much might be left in suspension is beyond me. I'm going to treat the fluid as 80% Ether, and see how it performs, both in ease of starting, and power output. Suspect I'll find the best compromise is somewhere between 80-90%.
Diesel fuel blending would be so much easier, if pure Di-ethyl Ether was still available to us non-drug users. Damn those drug users!
Bill
05-12-2016, 12:00 PM
#7
Welcome to the diesel world, newcomers from the Glow Engines areas!
Continuing some thoughts that started "over there," ....
JD Starter juice:- the MSDS quoted numbers may be confusing. Think of it this way: the % quoted is weight, not volume. Mentioned on the other area, and perhaps in answers to a few PMs - Specific Gravity of di-ethyl ether is about 0.6 0r 0.7. Translation? A volume of ether weighs 60% to 70% as much as the same volume of water does.
If the JD spray can quotes total weight of 7.0 ounces, and 20% of that is not specified, but is obviously the compressed propellant weight. That leaves 5.6 ounces of the ether which, (if we use an SG of 0.65) is about 8.6 fluid ounces of volume. That's almost 26% of a quart volume, if you milk it all out without loss in the form of spray.
If we capture another 1/4 of a can of JD ether, it makes the ether volume about 33% of a quart. Very nice, and using a graduated beaker, you can be as precise as you care to be.
Keep in mind that starter fluid spray is not critically dependent on purity or precision - it is mostly used to blow away while coaxing a mid-size agricultural or grounds-keeping diesel engine to start.
In the diesel area, quite a while back, I offered my method of milking the di-ethyl ether out of the JD cans with minimum loss, maximum safety and a reasonable process for storing any ether not needed for current fuel blending. I tried many methods, and like this one best.
Uses the 'Magic Straw' WD-40 spray tip. It fits the JD can.
... and two glass jars with metal screw-on caps. (Mark the jars for approximate volumes you'll need for your fuel.)
... Punch a hole in one cap, large enough to fit the spray straw.
.... Shake and spray the ether out through the straw, into that jar. Propellant gasses away around the straw, through the punched hole.
.... When you've captured as much as you need, stop spraying and change to the intact lid to seal the jar.
The rest of the ether in the can is as safe as it was before you started drawing it out. The cool surface of the glass jar helps liquefy the spray. Ether's volatility would cause a noticeable loss if the material didn't find a chill, in effect, immediately it is sprayed out of the can.
If you exhaust all the propellant in a can, seal the catch jar, invert the JD can (put the internal pickup tube OUT OF any remaining ether) and spray off any residual propellant pressure. Then you can safely punch a few holes around the rim on the JD can and pour the remaining ether into your catch jar.
Continuing some thoughts that started "over there," ....
JD Starter juice:- the MSDS quoted numbers may be confusing. Think of it this way: the % quoted is weight, not volume. Mentioned on the other area, and perhaps in answers to a few PMs - Specific Gravity of di-ethyl ether is about 0.6 0r 0.7. Translation? A volume of ether weighs 60% to 70% as much as the same volume of water does.
If the JD spray can quotes total weight of 7.0 ounces, and 20% of that is not specified, but is obviously the compressed propellant weight. That leaves 5.6 ounces of the ether which, (if we use an SG of 0.65) is about 8.6 fluid ounces of volume. That's almost 26% of a quart volume, if you milk it all out without loss in the form of spray.
If we capture another 1/4 of a can of JD ether, it makes the ether volume about 33% of a quart. Very nice, and using a graduated beaker, you can be as precise as you care to be.
Keep in mind that starter fluid spray is not critically dependent on purity or precision - it is mostly used to blow away while coaxing a mid-size agricultural or grounds-keeping diesel engine to start.
In the diesel area, quite a while back, I offered my method of milking the di-ethyl ether out of the JD cans with minimum loss, maximum safety and a reasonable process for storing any ether not needed for current fuel blending. I tried many methods, and like this one best.
Uses the 'Magic Straw' WD-40 spray tip. It fits the JD can.
... and two glass jars with metal screw-on caps. (Mark the jars for approximate volumes you'll need for your fuel.)
... Punch a hole in one cap, large enough to fit the spray straw.
.... Shake and spray the ether out through the straw, into that jar. Propellant gasses away around the straw, through the punched hole.
.... When you've captured as much as you need, stop spraying and change to the intact lid to seal the jar.
The rest of the ether in the can is as safe as it was before you started drawing it out. The cool surface of the glass jar helps liquefy the spray. Ether's volatility would cause a noticeable loss if the material didn't find a chill, in effect, immediately it is sprayed out of the can.
If you exhaust all the propellant in a can, seal the catch jar, invert the JD can (put the internal pickup tube OUT OF any remaining ether) and spray off any residual propellant pressure. Then you can safely punch a few holes around the rim on the JD can and pour the remaining ether into your catch jar.
Last edited by Lou Crane; 05-12-2016 at 12:09 PM.
05-12-2016, 04:31 PM
#8
I milk the cans as you do, Lou. I have been getting 8.5 fluid ounces of liquid ether from the can and use about 10oz to a quart of fuel. I shoot for around 31% ether by volume. I chill the ether can in the freezer for about a half hour - it slows the evaporation. I use a 16oz mason jar that I engraved with one ounce increments. This works really well.
05-12-2016, 07:13 PM
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I didn't feel very comfortable about puncturing a can of Ether with a nail, or metal scribe.
My method of spraying the contents via a plastic straw inserted into the nozzle of the JD can, and directly into a plastic graduated catch bottle from a beauty supply store seems much safer to me.
Unfortunately, the last 6 JD cans I bought did not have the enlarged opening in the nozzle that fit the WD-40 straw I robbed from another spray container. I've saved all the nozzles I could find from the earlier JD cans, and swap those into the new JD cans as I drain them. Hopefully, JD will switch back to the earlier nozzles before my supply of old nozzles wear out.
Of course, the extracted Ether (if not used immediately) is transferred to a tightly sealed metal can until I get around to mixing another batch of diesel fuel.
Bill
My method of spraying the contents via a plastic straw inserted into the nozzle of the JD can, and directly into a plastic graduated catch bottle from a beauty supply store seems much safer to me.
Unfortunately, the last 6 JD cans I bought did not have the enlarged opening in the nozzle that fit the WD-40 straw I robbed from another spray container. I've saved all the nozzles I could find from the earlier JD cans, and swap those into the new JD cans as I drain them. Hopefully, JD will switch back to the earlier nozzles before my supply of old nozzles wear out.
Of course, the extracted Ether (if not used immediately) is transferred to a tightly sealed metal can until I get around to mixing another batch of diesel fuel.
Bill
05-13-2016, 08:12 AM
#10
I had found a bag of spray tips and straws that fit the same style of can except the size of the stem on the can. I just used a twist drill the same size as the can's stem and by hand reamed the spray tip a little larger to fit the ether can's stem. This has worked well so far. I only extract the ether I need for the batch of fuel I'm making. I don't like relying on the thin rubber seal of a canning jar to keep the ether from leaking. I have one lid for the "milking" jar that I initially drilled one hole in. I found when I tried using the jar, I found the escaping propellant gas would cause the liquid ether to leak past the straw. Adding two more smaller holes now allows the propellant to escape and not blow the ether out. I too do not like the idea of puncturing the cans. There's enough propellant to extract every drop of ether from the can and then some, so I see no need to do it any different.
One thing I have noticed in running diesels (keep in mind I'm still pretty new at this) that I struggle to attain the maple syrup colored exhaust oil that so many folks have posted about on these forums. I've gotten conflicting information in regard to this and I figured it might be worth getting more opinions on the matter. I run a number of different engines and they all seem to have very dark residue. I've been taught to tune the needles to the best rpm and set the compression such that it runs good on top without going hard and yet still throttle (recover from idling for a short time) well. This is how I've been doing it. A friend of mine tunes his diesels by running much richer with as least compression as possible. I tried it this way, but I found the fuel economy went down considerably and the engines power output dropped considerably as well. If I tune the rich/undercompressed way, the oil color is medium brown but lack a lot of power. Tuning the way I was taught gave good power, good throttling, and reasonably good starting when warm, but the exhaust residue is very dark. I have some .20 sized conversions as well as several .45 sized conversions. I was using a 10x6 APC as a benchmark prop on the .20 sized engines and 13x6 APC as a benchmark prop on the .45s. More than 6" pitch doesn't really suit my intended usage, and going to a 1" bigger diameter doesn't suit either. I will say that a 14x6 on the .45 does give a brown exhaust residue, but the power produced isn't enough... So with all of this said, can anyone add some perspective on the exhaust residue issue? Should I alter my fuel mixture? The engines I'm running are K&B Sportster .20/.28, .45, Super Tigre GS45 ABC, G51 ring, and soon an OS .25FSR. All use Davis Diesel conversion heads. My fuel has been 31% ether, 22% castor oil, 47% kerosene or Jet A, and 2% Amsoil Cetane Boost. I mix one quart at a time, and yes I know my mixture comes out to 102%.. The 2% Amsoil is literally like 20mL or 2/3 fluid ounce.
I have enjoyed learning diesels and will find legitimate uses for my engines, but before I fly them I want to make sure I'm covering all of my bases and get my tuning procedure down pat.
One thing I have noticed in running diesels (keep in mind I'm still pretty new at this) that I struggle to attain the maple syrup colored exhaust oil that so many folks have posted about on these forums. I've gotten conflicting information in regard to this and I figured it might be worth getting more opinions on the matter. I run a number of different engines and they all seem to have very dark residue. I've been taught to tune the needles to the best rpm and set the compression such that it runs good on top without going hard and yet still throttle (recover from idling for a short time) well. This is how I've been doing it. A friend of mine tunes his diesels by running much richer with as least compression as possible. I tried it this way, but I found the fuel economy went down considerably and the engines power output dropped considerably as well. If I tune the rich/undercompressed way, the oil color is medium brown but lack a lot of power. Tuning the way I was taught gave good power, good throttling, and reasonably good starting when warm, but the exhaust residue is very dark. I have some .20 sized conversions as well as several .45 sized conversions. I was using a 10x6 APC as a benchmark prop on the .20 sized engines and 13x6 APC as a benchmark prop on the .45s. More than 6" pitch doesn't really suit my intended usage, and going to a 1" bigger diameter doesn't suit either. I will say that a 14x6 on the .45 does give a brown exhaust residue, but the power produced isn't enough... So with all of this said, can anyone add some perspective on the exhaust residue issue? Should I alter my fuel mixture? The engines I'm running are K&B Sportster .20/.28, .45, Super Tigre GS45 ABC, G51 ring, and soon an OS .25FSR. All use Davis Diesel conversion heads. My fuel has been 31% ether, 22% castor oil, 47% kerosene or Jet A, and 2% Amsoil Cetane Boost. I mix one quart at a time, and yes I know my mixture comes out to 102%.. The 2% Amsoil is literally like 20mL or 2/3 fluid ounce.
I have enjoyed learning diesels and will find legitimate uses for my engines, but before I fly them I want to make sure I'm covering all of my bases and get my tuning procedure down pat.
05-13-2016, 12:22 PM
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Can't help you there, as I haven't flown any diesel engines since my McCoy .049 trainer as a teen.
I do start and tune them for friends who fly theirs, but have always warmed them up completely before launch, and reduced the compression a bit before release. I like to find the compression and mixture range after warm up, set them about mid range, and then back off the compression a little before release. This seems to work well, but no doubt reduces the power and economy a bit.
Unfortunately, I can't hear as well now as I once did, so I have to be very careful to avoid over compression.
I may have to resort to drilling the nozzles of JD cans some day, so thanks for that tip.
Bill
I do start and tune them for friends who fly theirs, but have always warmed them up completely before launch, and reduced the compression a bit before release. I like to find the compression and mixture range after warm up, set them about mid range, and then back off the compression a little before release. This seems to work well, but no doubt reduces the power and economy a bit.
Unfortunately, I can't hear as well now as I once did, so I have to be very careful to avoid over compression.
I may have to resort to drilling the nozzles of JD cans some day, so thanks for that tip.
Bill
05-13-2016, 01:13 PM
#12
I don't use the nozzle from the JD can, the ones I have are probably for brake cleaner or something as the spray pattern is a straight stream without the straw. Don't drill the stem in the can, you would drill the spray tip itself to fit the stem on the can.
06-22-2016, 05:52 AM
#13
Agreed both propane and butane are flammable - however they gas off fairly quickly. I'm sure some stays in suspension, but are probably used more for a propellant than anything else. Squirt some propane from a bottle and the liquid evaporates almost instantly. Same for butane - comes out liquid but evaporated very quickly. I'm curious to see what you come up with for results. I've treated the JD as 100% ether and mixed my fuel at 31% ether, 22% castor, 47% kerosene or jet A, and 2% Amsoil Cetane Booster. Over 100%, I know. That extra 2% is only 2/3 of a fl. oz. it fits an old Acetone can perfectly.
06-24-2016, 04:07 PM
#14
I don't know if WD40 is a world wide commodity. So far in the 'transferred from Glow' posts, only Fiery is outside the USA. If it isn't available in Oz or other countries, I'd regret to hear. Reference to the John Deere product suggests that IT is available
The current WD40 spray cans have what they label a 'Smart Straw,'' which has two positions - straw straight out or down along the length of the can. The spray nozzle can either shoot a spray or shoot through the straw. I've not seen any leakage at the cap or outlet in either position.
The spray cap fits the JD Starting Ether can and its nipple perfectly. Haven't bought any WD or JD in a bit over a year. Can't promise this remains true... Very convenient for milking the JD can ether into a glass jar..
Before I found this system, I DID have a problem with the residual propellant/propane or /butane. It finished gassing of in flight. Talk about trying to set mixture and comp when the fuel tank is sealed except for the feed line to the needle valve...
Using the WD can straw seems to allow enough time to gas off the propellant, if not completely, then sufficiently. Haven't had the residual pressure problem since.
The current WD40 spray cans have what they label a 'Smart Straw,'' which has two positions - straw straight out or down along the length of the can. The spray nozzle can either shoot a spray or shoot through the straw. I've not seen any leakage at the cap or outlet in either position.
The spray cap fits the JD Starting Ether can and its nipple perfectly. Haven't bought any WD or JD in a bit over a year. Can't promise this remains true... Very convenient for milking the JD can ether into a glass jar..
Before I found this system, I DID have a problem with the residual propellant/propane or /butane. It finished gassing of in flight. Talk about trying to set mixture and comp when the fuel tank is sealed except for the feed line to the needle valve...
Using the WD can straw seems to allow enough time to gas off the propellant, if not completely, then sufficiently. Haven't had the residual pressure problem since.
06-28-2016, 04:10 PM
#16
...One thing I have noticed in running diesels (keep in mind I'm still pretty new at this) that I struggle to attain the maple syrup colored exhaust oil that so many folks have posted about on these forums. I've gotten conflicting information in regard to this and I figured it might be worth getting more opinions on the matter. I run a number of different engines and they all seem to have very dark residue. I've been taught to tune the needles to the best rpm and set the compression such that it runs good on top without going hard and yet still throttle (recover from idling for a short time) well. This is how I've been doing it. A friend of mine tunes his diesels by running much richer with as least compression as possible. I tried it this way, but I found the fuel economy went down considerably and the engines power output dropped considerably as well. If I tune the rich/undercompressed way, the oil color is medium brown but lack a lot of power. Tuning the way I was taught gave good power, good throttling, and reasonably good starting when warm, but the exhaust residue is very dark...
Good luck
George
06-29-2016, 11:08 AM
#17
Exhaust oil color - may vary with other things than settings...
Of course, too rich and overcompressed often produces dark goo. Kerosene quality seems to play a part to, too. #2 auto diesel seems to run cleaner if settings are nicely balanced, and it is less than 1/3 the price of fancy hardware store kerosene - which often seems to claim low-sulphur content.
I would expect a fuel for automotive, non-heavy truck, diesel use HAS to run cleaner and with less odor to be tolerable to ordinary drivers,
I've not tested it, but there is a popular claim that any kind of kerosene produces practically the same power for our purposes. If so, why waste money on boutique hardware store stuff, or camp stove heater fuel? How cleanly it burns for us is a more relevant item.
As to settings for flight - the accepted word is a bit leaner and higher compressed than for non-throttled use. Makes sense. Long idle or low part-throttle run segments could puddle fuel in the crankcase AND cool the engine to where recovery to higher RPM throttle can bog, at least initially and briefly.
For single speed use, I generally try for a sweet-spot for prop and air load conditions, trying various props, as well as settings. Seems to me that diesels can find a sweet spot at which vibration is noticeably reduced. I presume the combustion load profile and mechanical inertia loadings come into some kind of syncopation - partially countering each other. This is not often at absolute peak for the prop&load, but moderated slightly. When the prop and air load conditions place such an RPM in a band for desirable flying power and consistency, things are good.
On the limited types of diesels I've benched, such a sweet-spot can usually be found without much effort. I start at the leanest needle that allows solid running in all attitudes (static conditions check for uphill and downhill fuel feed variations.) Comp set about halfway between overcompression banging and loss of RPM by being too low.
As with throttle engine setting, a tad more comp and a tad richer to compensate for higher RPM as the prop unloads.
Works for me, mostly.
Of course, too rich and overcompressed often produces dark goo. Kerosene quality seems to play a part to, too. #2 auto diesel seems to run cleaner if settings are nicely balanced, and it is less than 1/3 the price of fancy hardware store kerosene - which often seems to claim low-sulphur content.
I would expect a fuel for automotive, non-heavy truck, diesel use HAS to run cleaner and with less odor to be tolerable to ordinary drivers,
I've not tested it, but there is a popular claim that any kind of kerosene produces practically the same power for our purposes. If so, why waste money on boutique hardware store stuff, or camp stove heater fuel? How cleanly it burns for us is a more relevant item.
As to settings for flight - the accepted word is a bit leaner and higher compressed than for non-throttled use. Makes sense. Long idle or low part-throttle run segments could puddle fuel in the crankcase AND cool the engine to where recovery to higher RPM throttle can bog, at least initially and briefly.
For single speed use, I generally try for a sweet-spot for prop and air load conditions, trying various props, as well as settings. Seems to me that diesels can find a sweet spot at which vibration is noticeably reduced. I presume the combustion load profile and mechanical inertia loadings come into some kind of syncopation - partially countering each other. This is not often at absolute peak for the prop&load, but moderated slightly. When the prop and air load conditions place such an RPM in a band for desirable flying power and consistency, things are good.
On the limited types of diesels I've benched, such a sweet-spot can usually be found without much effort. I start at the leanest needle that allows solid running in all attitudes (static conditions check for uphill and downhill fuel feed variations.) Comp set about halfway between overcompression banging and loss of RPM by being too low.
As with throttle engine setting, a tad more comp and a tad richer to compensate for higher RPM as the prop unloads.
Works for me, mostly.
Last edited by Lou Crane; 06-29-2016 at 11:12 AM.
06-29-2016, 03:31 PM
#18
I've used home heating kerosene (labeled K1) and I've also used Jet A. The Jet A mix is a little cleaner - little less soot... But that's the only real difference. Same power as he home heating kerosene which also produced the same power as Davis ABC mix; at least in one particular engine. Jet A is about $1 more per gallon and is harder to obtain, so I'll stick with the kerosene for now. I will try some pump diesel now that we are far enough into the summer season. The winter blended diesel should be all used up by now.
